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pub struct SharedSecret<C: Curve> { /* private fields */ }
Available on crate feature ecdh only.
Expand description

Shared secret value computed via ECDH key agreement.

Implementations

Use HKDF (HMAC-based Extract-and-Expand Key Derivation Function) to extract entropy from this shared secret.

This method can be used to transform the shared secret into uniformly random values which are suitable as key material.

The D type parameter is a cryptographic digest function. sha2::Sha256 is a common choice for use with HKDF.

The salt parameter can be used to supply additional randomness. Some examples include:

  • randomly generated (but authenticated) string
  • fixed application-specific value
  • previous shared secret used for rekeying (as in TLS 1.3 and Noise)

After initializing HKDF, use Hkdf::expand to obtain output key material.

This value contains the raw serialized x-coordinate of the elliptic curve point computed from a Diffie-Hellman exchange, serialized as bytes.

When in doubt, use SharedSecret::extract instead.

⚠️ WARNING: NOT UNIFORMLY RANDOM! ⚠️

This value is not uniformly random and should not be used directly as a cryptographic key for anything which requires that property (e.g. symmetric ciphers).

Instead, the resulting value should be used as input to a Key Derivation Function (KDF) or cryptographic hash function to produce a symmetric key. The SharedSecret::extract function will do this for you.

Trait Implementations

Executes the destructor for this type. Read more

NOTE: this impl is intended to be used by curve implementations to instantiate a SharedSecret value from their respective AffinePoint type.

Curve implementations should provide the field element representing the affine x-coordinate as secret_bytes.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Converts self into T using Into<T>. Read more

Causes self to use its Binary implementation when Debug-formatted. Read more

Causes self to use its Display implementation when Debug-formatted. Read more

Causes self to use its LowerExp implementation when Debug-formatted. Read more

Causes self to use its LowerHex implementation when Debug-formatted. Read more

Causes self to use its Octal implementation when Debug-formatted. Read more

Causes self to use its Pointer implementation when Debug-formatted. Read more

Causes self to use its UpperExp implementation when Debug-formatted. Read more

Causes self to use its UpperHex implementation when Debug-formatted. Read more

Formats each item in a sequence. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Pipes by value. This is generally the method you want to use. Read more

Borrows self and passes that borrow into the pipe function. Read more

Mutably borrows self and passes that borrow into the pipe function. Read more

Borrows self, then passes self.borrow() into the pipe function. Read more

Mutably borrows self, then passes self.borrow_mut() into the pipe function. Read more

Borrows self, then passes self.as_ref() into the pipe function.

Mutably borrows self, then passes self.as_mut() into the pipe function. Read more

Borrows self, then passes self.deref() into the pipe function.

Mutably borrows self, then passes self.deref_mut() into the pipe function. Read more

Should always be Self

Immutable access to a value. Read more

Mutable access to a value. Read more

Immutable access to the Borrow<B> of a value. Read more

Mutable access to the BorrowMut<B> of a value. Read more

Immutable access to the AsRef<R> view of a value. Read more

Mutable access to the AsMut<R> view of a value. Read more

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Mutable access to the Deref::Target of a value. Read more

Calls .tap() only in debug builds, and is erased in release builds.

Calls .tap_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_borrow() only in debug builds, and is erased in release builds. Read more

Calls .tap_borrow_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_ref() only in debug builds, and is erased in release builds. Read more

Calls .tap_ref_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_deref() only in debug builds, and is erased in release builds. Read more

Calls .tap_deref_mut() only in debug builds, and is erased in release builds. Read more

Attempts to convert self into T using TryInto<T>. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.